通过ANSYS软件建立二维雁列断层模型,采用粘弹性力学参数,建立摩擦系数接触单元,模拟10万年时间大尺度雁列走滑断层活动(地震相关活动),分析挤压条件下的断层活动特征,研究结果表明:①断层时空区域不同,所受应力也不同,接近贯通区域重合地区所受应力较大,粘滑运动剧烈,由贯通区域向断层两侧逐渐延伸,所受应力依次减小;②摩擦系数越小,地震发生频率越高,地震运动周期越短,则位错量相对较小,易发生震级较小地震;摩擦系数越大,地震发生频率越低,地震运动周期越长,则位错量相对较大,易发生震级较大地震;③给定的边界挤压速率越大,地震发生频率越高,地震运动周期越短,则位错量增大,易发生震级较大地震。
The two-dimensional geography fault model is built by ANSYS software. The viscoelastic mechanical parameters were used to establish the friction coefficient contact element, and the large-scale geese stride fault was simulated for 100 000 years (earthquake related activities). The characteristics of fault activity under compression conditions are analyzed. The results of the study show that:①Because the faults have different space-time zones, the stresses received are also different. The closer to the area where the penetrating regions overlap, the greater the stress is, and the stick-slip movement is also the most intense, extending from the penetrating zone to both sides of the fault. The stress received decreases in turn. ②The smaller the friction coefficient, the higher the frequency of earthquakes, and the shorter the motion period of the earthquake, but the smaller the amount of dislocations is, and the smaller the magnitude of the earthquake. The larger the friction coefficient, the lower the frequency of the earthquake. The longer the motion cycle of the earthquake, but the larger the amount of dislocations, the higher magnitude earthquakes are likely to occur. ③The higher the given boundary extrusion rate, the higher the frequency of earthquake occurrence, the shorter the motion cycle of the earthquake, the greater the amount of dislocations, and the higher magnitude of earthquakes.
2018,39(6): 23-30 收稿日期:2018-03-27
DOI:10.3969/j.issn.1003-3246.2018.06.004
基金项目:地震科技星火计划(项目编号:XH17007);2017河北省地震科技星火重点项目(项目编号:DZ20170109002);河北省研究生创新资助项目(项目编号:CXZZSS2017130)
作者简介:王时(1989-),男,硕士,主要从事地震形变监测研究工作
*通讯作者:王想(1980-),女,硕士,高级工程师,主要从事测震学、数字地震学和地震预测等工作
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